Problem: The arithmetic sequence $(a_i)$ is defined by the formula: $a_i = 1 - 5(i - 1)$ What is $a_{17}$, the seventeenth term in the sequence?
From the given formula, we can see that the first term of the sequence is $1$ and the common difference is $-5$ To find $a_{17}$ , we can simply substitute $i = 17$ into the given formula. Therefore, the seventeenth term is equal to $a_{17} = 1 - 5 (17 - 1) = -79$.